I'm not the maker of the extension, I just have made macros and setup package.
It's mark303 who have made it work with K-Meleon by adding a kplugin.
But I agree, I think the spellcheck ought to be in the official build with en-US dictionnary.
The other dictionaries (fr, de, es, cn) have to be included in their own locale build.
Curiously, I have heard talking or asking about other language builds (pt or br), and no news since a long time.
Isn't there any volunteers to work on locale builds, and to make K-Meleon universal?
Mozilla/5.0 (x11; U; Linux x86_64; fr-FR; rv:38.0) Gecko/20100101 Ubuntu/12.04 K-Meleon/76.0
Mail : alain [dot] aupeix [at] wanadoo [dot] fr
Ubuntu 12.04 - Gramps 3.4.9 - Harbour 3.2.0 - Hwgui 2.20-3 - K-Meleon 76.0 rc